Many of today's vehicular headlights have for some time included either or both a light shield or a heat shield with the former operative to reduce glare when facing theretoward and the latter operative to absorb heat being emitted from the light source that characteristically extends, at least in part, into the cavity within the headlight frame such as in the case of sealed beam construction and more commonly in connection with the low beam member of a sealed beam construction well known to those skilled in the art of vehicular headlights.
Vehicular headlights have heretofore been manufactured in large part from plastic and vacuum metalized plastic materials well known to those skilled in the art. Lately it has been the practice to provide vehicular headlights with a clear lens primarily for styling purposes but which characteristically increases the degree of glare to which a viewer is exposed and which has been reduced by incorporating a light shield operative to shield the light source from a viewer in front of the headlight looking heretoward and to assist in the photomatic properties of casting light from the light source onto the headlight reflector such that the viewer is exposed primarily to reflected light having reduced glare.
Because of the close proximity of the light shield to the light source, they have heretofore been characteristically manufactured from metal so as to withstand heat radiated from the light source.
Prior art heat shields have heretofore been located outside of the light shield and most commonly have been positioned above the light source due to the tendency for heat to rise upwardly within the headlight interior.
Prior art practices for minimizing glare when facing directly towards a lighted vehicular headlight are disclosed for example in U.S. Pat. No. 4,679,127 in which the end of the light source (filament bulb) is contacted with an opaque light absorbing material and in U.S. Pat. No. 4,740,875 in which the inside of the lens is configured to reduce glare in addition to the end of the light source being coated with an opaque light absorbing material, the disclosures of both of which are incorporated herein by reference.
An example of an automotive headlamp having a glare shield disposed about the light source is disclosed in U.S. Pat. No. 4,754,373 and a example of a rectangular headlight having a light shield disposed outwardly of the end of a light emitting filament is disclosed in U.S. Pat. No. 4,029,985, the disclosures of both of which are incorporated herein by reference.
Examples of automotive headlamps that employ both a light and a heat shield can be found in U.S. Pat. Nos. 4,642,514 and 5,204,578, the disclosures of both which are incorporated herein by reference. None, however, provide a combination wherein a heat shield is positioned within a light shield as is the case in the present invention for in both U.S. Pat. Nos. 4,642,514 and 5,204,578, the heat shield is provided as a separate member positioned below the light filament and, in U.S. Pat. No. 4,642,514 the combination of a heat shield and a light shield is provided in the form of layers in the inside of the headlamp lens.
In contrast to the prior art, the present invention provides the combination of a light shield and a heat shield in which the heat shield is positioned within the light shield in spaced-apart relationship thereto with the combination being easily secured about the light source within the headlight without the cost of complexity of having to apply layers to the inside of the headlamp lens or having to secure the heat shield and the light shield separately to the headlight as well as eliminating the need to manufacture the light shield exclusively from metal where such is desired since the heat shield is disposed intermediate the light source and the light shield with the added thermal protection provided by an open air gap therebetween.